"Fusilier Rigby was a dedicated and professional young man whose life was taken in the most casual, brazen and horrific fashion, in broad daylight on the streets of London.”

Speaking outside the Old Bailey, where the two week trial took place, Sue Hemming, Head of Special Crime and Counter Terrorism at the Crown Prosecution Service, said: "The murder of Fusilier Rigby was brutal and its perpetrators carried out one of the most savage offences ever prosecuted by our counter terrorism lawyers.”

The extremists admitted killing the father-of-one but tried to argue it was legitimate because they were “soldiers” attacking an enemy in the war between Muslims and the British public.

But the jury had been told to ignore the defence by the trial judge.

The pair were both cleared of a attempting to murder a police officer.

Assistant Metropolitan Commissioner Cressida Dick, who heads counter-terrorism operations, said: “What happened to Lee that day has shocked and sickened people in London, the UK and far beyond. There’s nothing that can justify those atrocious actions.”

Theresa May, the Home Secretary, said: “The sickening and barbaric murder of Drummer Lee Rigby united the entire nation in condemnation and I welcome the jury's decision.

"But we must not forget that this appalling and public act of violence and terror also robbed his family and loved ones of a brave, young man with his life ahead of him. My thoughts are with them at this difficult time.

"Violence and extremism of any kind have absolutely no place in our society and cannot be justified.”

The soldier, a father of one, was a member of the Corps of Drums with the 2nd Battalion, the Royal Regiment of Fusiliers.

Lieutenant Colonel Jim Taylor described the 25-year-old, who was with Second Battalion, The Royal Regiment of Fusiliers, as "a true warrior" and called his brutal death "a cruel tragedy"